. >>> officials say the next big attack on the u.s. will likely be online. now lawmakers on the hill want to know if homeland security is prepared for it. we have more from capitol hill. >> reporter: at a hearing on capitol hill. a cyber attack is one of the greatest threats to u.s. national security. >> it is today possible to be a great warrior with nothing but your slippers and your bedroom and the desire to bring down some aspect of public or private infrastructure related to the internet. >> reporter: lawmakers want to know if homeland security is prepared for a future attack in the digital world and they say the biggest threat comes from china. >> then cia director leon panetta called cyber security the battleground for the future. >> this has got to have a lot more attention placed upon it. we certainly don't want to have the kind of incident that we would all regret. >> reporter: the obama administration says the nation's critical infrastructure is under constant attack by criminals. it would harm consumers and government agent is posing a -- agencie